When Robert Hanssen was arrested for espionage in 2001, many said at the time his story would be perfect for a motion picture. They were right. “Breach” doesn’t move much further than hairy eyeballs and panicked sprints, but it clicks together beautifully, lead by an impossibly crusty lead performance from Chris Cooper.

How does one make two men sitting in an office pontificating on the nature of loyalty a fingernail-chewing experience? Ask Billy Ray, the director of “Breach.” He’s managed to take the slow, methodical process of surveillance and twist it into a wonderful new film.

Robert Hanssen (Chris Cooper) is a respected F.B.I. agent with 25 years of service to his country. Eric O’Neill (Ryan Phillippe) is a young agent just starting his career assigned to watch Robert’s every move, reporting to his superiors (including Laura Linney and Dennis Haysbert) with the details. Told he’s simply keeping tabs on Robert’s computer usage, Eric finds he’s drawn to the elder agent’s devout religious life and cologne of honor. Loyalties are soon tested when Eric learns the real reason behind his observation: Robert’s 15-year-long reign as American’s most entrenched spy.

The battlefield of espionage and underhanded governmental reach was given a thorough treatment in December’s “The Good Shepherd,” but “Breach” pushes the camera in closer. This is essentially a two character play, watching Eric and Robert dance around the obvious tension in the room as they try to sniff each other out. Men of honor and ambition, the restlessness of the film comes from witnessing two personalities being tested both in the office and at home.

It’s to Ray’s massive credit that he can turn a true-life arrest, in which the ending was widely reported, into a picture of staggering suspense. The anxiety is found in the little moments: will Eric be able to stall Robert long enough for information to be harvested? Does Robert understand the extent of the deception to catch him? Ray (“Shattered Glass”) maintains the film’s simmer even through the most obvious ploys at keeping the audience at the edge of their seats. Heavens, this is a film about two guys in suits talking for 110 minutes. How could there be such tension? “Breach” is something of a cinematic miracle in the way it uses silence as a deadly weapon.

In this power play, the roles need a punch from the best, and there’s nobody else who can stir together utter contempt with bitter patriotism quite like Chris Cooper. His reading of Robert Hanssen is a study in the meticulousness of paranoia. Hanssen was a religious man who pushed around his spiritual weight and enjoyed the flag-waving pride of his office. He also was a closet deviant with a major hankering for Catherine Zeta-Jones and sharing marital sex tapes with friends. How Cooper is able to incorporate every sordid detail of Hanssen’s life and be able to fashion a character the audience can still approach is remarkable. Cooper doesn’t make Hanssen sympathetic; the actor turns the traitor into something far more interesting: a complex human being.

While lacking the screen dynamism of Cooper, Philippe doesn’t embarrass himself at all here. Phillippe’s inherent stillborn emotional range finds a home in Eric’s bewilderment and continuous professional perspiration, and he makes a strong center of conscience for the picture, even when Cooper acts circles around him.

The performances only carry “Breach” halfway; the wild, painfully true story of Robert Hanssen’s treachery fills in the rest of the picture with wide-eyed alarm. It turns out all the terrorism in the world isn’t nearly as frightening as a churchgoing American with unfiltered access to state secrets and an ego to massage.